Sparticle and Higgs Production and Detection at LEPII in two Supergravity Models

Abstract

We study the most promising signals for supersymmetry at LEPII in the context of two well motivated supergravity models: (i) the minimal $SU(5)$ supergravity model including the stringent constraints from proton stability and a not too young Universe, and (ii) a recently proposed string-inspired no-scale flipped $SU(5)$ supergravity model. Our computations span the neutralino, chargino, slepton, and Higgs sectors together with their interconnections in this class of models. We find that the number of `mixed' (1-lepton + 2-jets + $\slash{p}$) events occuring in the decay of pair-produced charginos (${\chi }_1^{\pm }$) is quite significant (per ${\cal L}=100\ipb$) for both models and that these predictions do not overlap. That is, if $m_{χ^\pm_1}<100\GeV$ then LEPII should be able to exclude at least one of the two models. In the no-scale flipped $SU(5)$ model we find that the number of acoplanar di-electron events from selectron pair production should allow for exploration of selectron masses up to the kinematical limit and chargino masses indirectly as high as 150 GeV. We find that the cross section $e^{+}{e}^{-}\to Z^{\ast }h$ deviates negligibly from the SM result in the minimal model, whereas it can be as much as $1/3$ lower in the flipped model. The usually neglected invisible mode $h\to {\chi }_1^0{\chi }_1^0$ can erode the preferred $h\to 2\mathrm{jets}$ signal by as much as $40\%$ in these models. We conclude that the charged slepton sector is a deeper probe than the chargino/neutralino or Higgs sectors of the flipped $SU(5)$ model at LEPII, while the opposite is true for the minimal $SU(5)$ model where the slepton sector is no probe at all.

20 pages plus 13 postscript figures (included); CTP-TAMU-89/92, CERN-PPE/93-16

References in corpus (12)

• Nucleon Decay in the Minimal Supersymmetric $SU(5)$ Grand Unification
• Predictions in SU(5) Supergravity Grand Unification with Proton Stability and Relic Density Constraints
• Testing the Higgs Sector of the Minimal Supersymmetric Standard Model at Large Hadron Colliders
• Cosmological Constraints and SU(5) Supergravity Grand Unification
• Aspects of Radiative Electroweak Symmetry Breaking in Supergravity Models
• Flipped Heavy Neutrinos from the Solar Neutrino Problem to Baryogenesis
• Supersymmetry Tests at Fermilab: A Proposal
• Proton Decay and Cosmology Strongly Constrain the Minimal SU(5) Supergravity Model
• Collider discovery limits for supersymmetric Higgs bosons
• Improved LEP lower bound on the lightest SUSY Higgs mass from Radiative Electroweak Breaking and its Experimental Consequences
• Troubles with the Minimal SU(5) Supergravity Model
• Proposed Tests for Minimal SU(5) Supergravity at Fermilab, Gran Sasso, SuperKamiokande, and LEP

Cited by in corpus (23)

• The Minimal Model of Nonbaryonic Dark Matter: A Singlet Scalar
• Cosmological Relic Density from Minimal Supergravity with Implications for Collider Physics
• Anomaly-Free Gauged R-Symmetry
• The MSSM invisible Higgs in the light of dark matter and g-2
• Detecting an Invisibly Decaying Higgs Boson at a Hadron Supercollider
• Novel Higgs Decays and Dark Matter in the E(6)SSM
• Supersymmetry Studies at Future Linear $e^{+}{e}^{-}$ Colliders
• The strongest experimental constraints on SU(5)xU(1) supergravity models
• Exotic Higgs decays in the E6 inspired SUSY models
• SUSY Higgs at the LHC: Effects of light charginos and neutralinos
• Master equations for effective Hamiltonians
• Towards a unified string supergravity model
• Experimental aspects of SU(5)xU(1) supergravity
• Prospects for Supersymmetry at LEP2
• Higgs Mass Bounds Separate Models of Electroweak Symmetry Breaking
• Updated: Higgs Mass Bounds Separate Models of Electroweak Symmetry Breaking
• Supersymmetry: From the Fermi Scale to the Planck Scale
• A string no-scale supergravity model and its experimental consequences
• A Layman's guide to SUSY GUTs
• Status of the superworld: from theory to experiment
• New Precision Electroweak Tests of SU(5) x U(1) Supergravity
• SUSY signals at HERA in the no-scale flipped SU(5) supergravity model
• Exploring the Yukawa Unified Minimal Supergravity Model at the Tevatron, LEP-II, and the LHC